Radiation-setting composition containing (meth)acrylic copolymers containing acid groups

Abstract

Radiation-setting compositions suitable for the formation of LCD spacers or protective layers which are excellent in photosetting properties (requiring no heat-setting) and development properties, have high adhesiveness to substrates and excellent mechanical characteristics, remain stable over a long storage time and show excellent working condition-dependency. Such a radiation-setting composition for the formation of LCD spacers or protective layers comprises a (meth)acrylic acid-based copolymer having an acid value of 30 to 200 and a glass transition temperature of −30 to 180° C., a (meth)acrylate-based compound obtained by copolymerizing a monomer having a specific structure with a monomer at least having an acidic group, a radiation-sensitive compound and a solvent.

What is claimed is:  
     
       1. A radiation-setting composition for liquid crystal display (LCD) spacers which comprises: 
       (A) a (meth)acrylic copolymer comprising (meth)acrylic acid, said (meth)acrylic copolymer having an acid value of 30 to 200 and a glass transition temperature of −30 to 180° C.;  
       (B) a (meth)acrylic copolymer obtained by copolymerizing a monomer represented by the following formula (I) with a vinyl monomer at least having an acidic group;  
       (C) a radiation-sensitive compound; and  
       (D) a solvent:                    
       wherein R represents a hydrogen atom or a methyl group; and R 1  to R 5  each represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 7 carbon atoms or an acryl group having 6 to 12 carbon atoms. 
     
     
       2. The radiation-setting composition for LCD spacers as claimed in claim  1 , wherein said (meth)acrylic copolymer (A) is one represented by the following formula (2-1), (2-2) or (2-3) and having a weight-average molecular weight (Mw) of 3,000 to 300,000:                    
       wherein R 7  represents an alkyl group with 1 to 18 carbon atoms, a phenyl group having an alkyl group with 1 to 4 carbon atoms, a phenyl group having an alkoxy group with 1 to 4 carbon atoms, an aryl group with 6 to 12 carbon atoms or an aralkyl group with 7 to 12 carbon atoms; R 8  to R  10  each represents a hydrogen atom or a methyl group; n is 2 or 3; 
       a, b: a/b=5/5 to 9/1;  
       c, d, e: c/(d+e)=5/5 to 9/1, d/e=9/1 to 2/8; and  
       f, g, h, k: (f+k)/(g+h)=5/5 to 9/1, g/h=9/1 to 2/8, f/k=9/1 to 1/9.  
     
     
       3. The radiation-setting composition for LCD spacers as claimed in claim  1 , wherein said (meth)acrylic copolymer (A) is contained at a ratio of from 20 to 80% by weight based on the total solid components of the composition. 
     
     
       4. The radiation-setting composition for LCD spacers as claimed in claim  1 , wherein said (meth)acrylic copolymer (B) is contained at a ratio of from 5 to 9% based on the total solid components of the composition. 
     
     
       5. A radiation-setting composition for LCD protective layers which comprises: 
       (A) a (meth)acrylic copolymer comprising (meth)acrylic acid, said (meth)acrylic copolymer being represented by the following formula (2-1), (2-2) or (2-3), having a weight-average molecular weight (Mw) of 3,000 to 300,000 and having an acid value of 30 to 200 and a glass transition temperature of −30 to 180° C.;  
       (B) a (meth)acrylic copolymer obtained by copolymerizing a monomer represented by the following formula (I) with a vinyl monomer at least having an acidic group;  
       (C) a radiation-sensitive compound; and  
       (D) a solvent:                    
       wherein R 7  represents an alkyl group having 1 to 18 carbon atoms, a phenyl group having an alkyl group with 1 to 4 carbon atoms, a phenyl group having an alkoxy group with 1 to 4 carbon atoms, an aryl group with 6 to 12 carbon atoms or an aralkyl group with 7 to 12 carbon atoms; R 8  to R 10  each represents a hydrogen atom or a methyl group; n is 2 or 3; 
       a, b: a/b=5/5 to 9/1;  
       c, d, e: c/(d+e)=5/5 to 9/1, d/e=9/1 to 2/8; and  
       f, g, h, k: (f+k)/(g+h)=5/5 to 9/1, g/h=9/1 to 2/8, f/k=9/1 to 1/9                    
       wherein R represents a hydrogen atom or a methyl group; and R 1  to R 5  each represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 7 carbon atoms or an aryl group having 6 to 12 carbon atoms.